<?php 
 
//自定义登录页面CSS
function custom_login() {
    echo '<link rel="stylesheet" type="text/css" href="' . get_bloginfo('template_directory') . '/assets/css/login_style.css" />';

}
add_action('login_head', 'custom_login');




//自定义登录页面LOGO提示为任意文本
function custom_loginlogo_desc($url) {
    return 'WordPress大学'; //修改文本信息
}
add_filter( 'login_headertext', 'custom_loginlogo_desc' );

//在登录框添加额外的信息
function custom_login_message() {
    echo '<p>欢迎来到'.get_bloginfo('name').'，请登录后下载本站资源</p><br />';
}
add_action('login_form', 'custom_login_message');

//自定义底部信息
add_action('login_footer', 'custom_html');
function custom_html() {
    echo '<p class="copyright_login">© ' . get_bloginfo('url').'</p>';
echo "<div id='large-header' class='large-header'><canvas id='demo-canvas'></canvas></div><script>
	(function() {

    var width, height, largeHeader, canvas, ctx, circles, target, animateHeader = true;
    // Main
    initHeader();
    addListeners();

    function initHeader() {
        width = window.innerWidth-20;
        height = window.innerHeight;
        target = {x: 0, y: height};

        largeHeader = document.getElementById('large-header');
        largeHeader.style.height = height+'px';

        canvas = document.getElementById('demo-canvas');
        canvas.width = width;
        canvas.height = height;
        ctx = canvas.getContext('2d');

        // create particles
        circles = [];
        for(var x = 0; x < width*0.5; x++) {
            var c = new Circle();
            circles.push(c);
        }
        animate();
    }

    // Event handling
    function addListeners() {
        window.addEventListener('scroll', scrollCheck);
        window.addEventListener('resize', resize);
    }

    function scrollCheck() {
        if(document.body.scrollTop > height) animateHeader = false;
        else animateHeader = true;
    }

    function resize() {
        width = window.innerWidth-20;
        height = window.innerHeight;
        largeHeader.style.height = height+'px';
        canvas.width = width;
        canvas.height = height;
    }

    function animate() {
        if(animateHeader) {
            ctx.clearRect(0,0,width,height);
            for(var i in circles) {
                circles[i].draw();
            }
        }
        requestAnimationFrame(animate);
    }

    // Canvas manipulation
    function Circle() {
        var _this = this;

        // constructor
        (function() {
            _this.pos = {};
            init();
        })();

        function init() {
            _this.pos.x = Math.random()*width;
            _this.pos.y = height+Math.random()*100;
            _this.alpha = 0.1+Math.random()*0.3;
            _this.scale = 0.1+Math.random()*0.3;
            _this.velocity = Math.random();
        }

        this.draw = function() {
            if(_this.alpha <= 0) {
                init();
            }
            _this.pos.y -= _this.velocity;
            _this.alpha -= 0.0005;
            ctx.beginPath();
            ctx.arc(_this.pos.x, _this.pos.y, _this.scale*10, 0, 2 * Math.PI, false);
            ctx.fillStyle = 'rgba(255,255,255,'+ _this.alpha+')';
            ctx.fill();
        };
    }

})();
</script>";
}

 
?>